How Hacker News ranking works: scoring, controversy, and penalties (2013)

Hacker News uses a scoring system where each user can upvote or downvote a story, with upvotes increasing the story's score and downvotes decreasing it. The score is then used to rank the story. Users are penalized for downvoting too many stories that eventually become popular, and their downvotes are reduced in weight. The algorithm also has a 'karma' system, where users earn points for creating stories or comments, but are penalized for creating low-quality content. The system is designed to prevent abuse and maintain a healthy discussion environment. The algorithm's details are not publicly disclosed, but it is known to use a combination of score and time to determine the ranking of a story.